Tuesday, July 23, 2013

Illinois Corn: High Daytime Temps Not a Big Concern

AgFax.Com - Your Online Ag News Source


The spike of above-average daytime temperatures throughout much of Illinois during the third week of July should not raise concerns for the corn crop as most areas had enough water in the soil to carry crops through that week, said University of Illinois professor of crop sciences Emerson Nafziger.

However, higher than normal night temperatures during the past week might have hurt pollination success in areas where soils are starting to dry out, Nafziger said.

“The heavy silking that preceded the full emergence of tassels, as noted in recent years, is very much evidenced again this year. This means there should be little concern about having silks present when pollen is being shed,” he said.


Nafziger said that 21 percent of the Illinois corn crop was pollinating on July 14, and this moved to 64 percent by July 21. “Planting was concentrated in the third week of May this year, so pollination is also occurring relatively quickly. That’s a week or so later than normal,” he added.

In some fields planted in mid-May or later, especially those planted at high populations, stalk diameter is noticeably smaller than often seen in earlier-planted corn. Later-planted corn with adequate soil moisture often grows taller than early-planted corn because of higher temperatures during internode elongation. Because late planting doesn’t increase plant weight, stalks end up tall and on the thin side, Nafziger said.

“Plants with smaller stalks often have less leaf area, and thus less ability to set and fill a large ear. It’s too early to know if this will decrease yield potential, but it is one of the ways in which late planting can lead to lower yields,” he said.

A return to better soil moisture conditions along with lower night temperatures over the next two weeks should allow good kernel set. After a wet June, Nafziger said soil moisture is becoming a concern in some places. July rainfall has been less than normal over much of Illinois, with less than an inch so far in parts of western and northern Illinois.

“The soil water supply was good coming into July, but how well the crop is tapping into this supply will make a difference as we move into the second half of the season,” Nafziger said. “Fields that were planted have had a chance to produce a good crop canopy, which in turn enabled deeper root growth. Roots may not be as extensive as they were in July 2012, but as we saw last year, good root systems don’t help when there’s no available water in the soil.”

The available water supply is not as certain for later-planted crop which won’t pollinate until late July or early August. These plants are in mid-vegetative stages and are showing mid-afternoon drought stress symptoms (leaf curling) in areas where recent rainfall has been limited. “This crop has not grown enough to have used up the available soil water to 3 or 4 feet deep. Rather, the root system is simply not as deep or as well connected as it would be had planting been done earlier or if soils had not been so wet earlier,” Nafziger explained.

Another concern with wet weather earlier in the spring is nitrogen supply for the crop. While leaf color remains good in areas with adequate soil water and where the crop has continued to grow well, in areas where soils have dried and some drought effects are starting to appear, leaf color has lightened some. Nafziger said rainfall in these areas should return leaf color to normal green. However if plants have been under stress from lack of nitrogen during the pollination period, he cautioned that success of kernel set can be lowered.

“It is possible that nitrogen loss in some lower-lying parts of fields may mean shortages for the crop, even after root systems recover. Supplemental applications of nitrogen have been made in some such areas, usually as urea, and sometimes with urease inhibitor. Such applications might produce enough added yield to provide a positive return if they are made before or even during pollination, but are likely to be effective only when rain moves the nitrogen into the soil,” he said.

As crops move through pollination and into the grain filling stages, the major concern will be how well the leaf canopy holds up in providing maximum amounts of photosynthate (sugars) to fill kernels.

Soil water supply will be the major factor, followed by leaf health and nutrient supply, Nafziger said. “We expect the crop to take about 8 weeks to reach maturity after pollination is complete, and maintaining green, healthy leaves through this period is the only way to maximize kernel fill and yield. If the crop takes less time from pollination to maturity, it will have stopped filling prematurely and will produce lower yields,” he said.

Tags: , , , , , ,


Leave a Reply

Name and Email Address are required fields. Your email will not be published or shared with third parties.

Sunbelt Ag News

    DTN Cotton Open: Trades Slightly Lower in Quiet Dealings4-21

    4 Factors That Have Reshaped Agriculture in Last 10 Years — DTN4-21

    Texas Explosion Prompts Subtle Changes in Fertilizer Industry — DTN4-21

    DTN Livestock Open: Cattle Futures to Begin Lower4-21

    DTN Grain Open: Lower Start Across Board4-21

    Flint on Crops: Reniform Nematode Continues to Plague Us4-21

    Keith Good: Citrus Disease Bites Florida; USDA to Track All PEDv Cases4-21

    Southern Grain: Freeze Effects? Corn Planting Slogs Along – AgFax4-19

    Rose On Cotton: Export Sales, Shipments Bear Watching4-18

    Arctic Warming Tied to Our Extreme Weather? Maybe. – DTN4-18

    Do Soybeans Need Nitrogen?4-18

    Is There An Advantage To More Corn Acres in Your Rotation? Yes and No.4-18

    Texas Rice: Garry McCauley Retires After 39 Years and Many Accomplishments4-18

    Rice Farmers In Midsouth Looking For A Break In The Weather – AgFax4-18

    Cleveland on Cotton: Nervous Market Nellies; Chinese Plant 20-25% Less4-17

    Grain TV: River Basis Levels See Large Rise4-17

    DTN Livestock Close: Meat Futures Take Wide Swings Before Exiting for Holiday4-17

    Doane Cotton Close: Heavy Volatility Continues in Old-Crop Prices4-17

    Chumrau on Wheat: World Supplies Get a Lift, but U.S. Stocks Look Tight4-17

    AFB Grain-Soybean Close: Wheat Higher, Corn Down, Beans Mixed4-17

    AFB Cotton Close: New-Crop Continues to Show Strength4-17

    AFB Rice Close: Across the Board Losses4-17

    DTN Cotton Close: Finishes Mixed Ahead of Long Weekend4-17

    Mississippi: MSU Offers Four Deer Management Workshops This Summer4-17

    Mapping the Farm Bill: Voting Changes in the House of Representatives4-17

    DTN Grain Close: Markets Mixed Ahead of Holiday Weekend4-17

    USDA: Peanut Price Highlights4-17

    Texas: Grain Grading Workshops, Amarillo, May 6-74-17

    Mississippi: State Soybean Value Grew $1B Since 20064-17

    U.S. Drought Outlook: Improvement Expected in Midwest, Central and Southern Great Plains4-17

    Farm Finances Rate an ‘A’ For Now, but Questions Linger — DTN4-17

    DTN Livestock Midday: Sharp Losses Hold in Cattle Trade4-17

    Mississippi: Top of the List for Water Resouces4-17

    DTN Grain Midday: Corn, Soybeans Move Lower4-17

    U.S. Grain Transportation: Upper Mississippi Navigation Improves4-17

    Resistant Palmer Pigweed: What People Need To Know Before It Hits – AgFax4-17

    Chemical Safety Board Plans Meeting in West, Texas — DTN4-17

    West, Texas, Recovers and Rebuilds with Cautious Approach — DTN4-17

    U.S. Energy: Oil and Gas Spending Favors Exploration, Development4-17

    Gasoline Prices: Average Jumps 6 Cents4-17

    Propane Stocks: Increase by 0.8M Barrels4-17

    Diesel Prices: Average Down a Penny4-17

    Victims of Texas Fertilizer Plant Explosion Remembered — DTN4-17

    Keith Good: Beige Book — Observations on Ag Economy4-17

    “Agricultural Adventure” Educate Public on Modern Farming – DTN4-16

    International Buying and Selling a Balancing Act to Get the Best Deal – DTN4-16

    Weather Woes Stretch from Iowa to Florida — DTN4-16

    Brazil’s Ports Remain Orderly with Good Luck, Favorable Conditions – DTN4-15

    Texas: Conservation Farming Meeting Weslaco, April 294-15

    Welch on Wheat: Cool Temperatures Hit Drought Stressed Crop4-15

    N.C. State University Leads Research into Kudzu Bug Host Preferences4-15

    Welch on Grain: Corn Planting in Line with 30 Year Average4-15

    Fertilizer Prices on the Rise but Still Lower Than Last Few Years4-15

    USDA: Weekly National Peanut Prices4-15

    Louisiana: Wildlife Field Day, Clinton, May 34-15

    Sign Ups Begin for USDA Disaster Assistance Programs4-15

    DTN Fertilizer Trends: Rail Delays Affecting Prices in Upper Midwest4-15

    Sunbelt Ag Events

     

    About Us

    AgFax.Com covers agricultural trends and production topics, with an emphasis on news about cotton, rice, peanuts, corn, soybeans, wheat and tree crops, including almonds, pecans, walnuts and pistachios.

      

    This site also serves as the on-line presence of electronic crop and pest reports published by AgFax Media LLC (formerly Looking South Communications).

        

    Click here to subscribe to our free reports.

      

    We provide early warnings and confirmations about pests, diseases and other factors that influence yield. Our goal is to quickly provide farmers and crop advisors with information needed to make better and more profitable decisions.

         

    Our free weekly crop and pest advisories include:

    • AgFax Midsouth Cotton, covering cotton production and news in Alabama, Arkansas, Louisiana, Mississippi, Tennessee and Missouri.

    • AgFax Southeast Cotton, covering cotton production and news in Alabama, Florida, Georgia, North Carolina, South Carolina and Virginia.

    • AgFax Southwest Cotton (new for 2013!), covering cotton production and news in Texas, Oklahoma, Kansas and New Mexico.

    • AgFax West (formerly MiteFax: SJV Cotton), covering California cotton, alfalfa, tomatoes and other non-permanent crops in California's Central Valley.

    • AgFax Rice covering rice production and news in Arkansas, Louisiana, Mississippi, Missouri and Texas.

    • AgFax Peanuts, covering peanut production in Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Texas and Virginia.

    • AgFax Southern Grain: covering soybeans, corn, milo and small grains in Southern states.

    • AgFax Almonds, covering almonds, pistachios, walnuts and other tree crops in California's Central Valley.

    • AgCom 101, providing guidance to ag professionals involved in social media.

    Our newsletters are sponsored by the following companies: FMC Corporation Chemtura Dow AgroSciences.

          

    Mission statement:

    Make it as easy as possible for our community of readers to find and/or receive needed information.

              

    Contact Information:

    AgFax Media. LLC

    142 Westlake Drive Brandon, MS 39047

    601-992-9488 Office 601-992-3503 Fax

    Owen Taylor Debra L. Ferguson Laurie Courtney

          

    Circulation Questions?

    Contact Laurie Courtney